Conditional Indicators

If

sufficient

When

sufficient

each

sufficient

every

sufficient

all

sufficient

in order to

sufficient

any

sufficient

the only

sufficient

only

necessary

only if

necessary

only when

necessary

must

necessary

depends

necessary

requires

necessary

then

necessary

needs

necessary

always

necessary

unless

sufficient; negates sufficient (if not)

until

sufficient; negates sufficient (if not)

without

sufficient; negates sufficient (if not)

if not

sufficient; negates sufficient

Cannot/Can't

necessary; negates necessary (then not)

Must not

necessary; negates necessary (then not)

Never

necessary; negates necessary (then not)

Then not

necessary; negates necessary

No

sufficient; negates necessary (torpedo)

No one

sufficient; negates necessary (torpedo)

Nobody

sufficient; negates necessary (torpedo)

Nothing

sufficient; negates necessary (torpedo)

Nowhere

sufficient; negates necessary (torpedo)

if and only if

biconditional; both sufficient and necessary (double arrow)

when and only when

biconditional; both sufficient and necessary (double arrow)

if but only if

biconditional; both sufficient and necessary (double arrow)